Wheelchairs are often propelled by the user's gripping and pushing on a circular member or handwheel attached to the outside of each wheel, of a diameter sightly smaller than that of the wheel. There is a direct drive from the handwheel to the chair wheel.
Certain disadvantages occur, such as when moving uphill, or downhill, or up and down ramps. In particular, moving uphill can present considerable difficulty to the user, in that the user may not have sufficient strength to move the handwheels, and thus the chair wheels. Also, when moving uphill a safety factor can occur in that there is the strong possibility of a wheelchair tending to run backwards, downhill, if the user loses hold on the handwheel, or for other causes.
Further, difficulty can be experienced in getting in and out of chairs in that the footrests obstruct any easy access and egress. Pivotally mounted footrests are provided but it is usually extremely difficult and often impossible for the user to pivot the footrest up and down, particularly when the user is sitting in the chair.